Data Item _cell.reciprocal_angle_alpha
Browse:
General 
- Item name
- _cell.reciprocal_angle_alpha
- Category name
- cell
- Attribute name
- reciprocal_angle_alpha
- Required in PDB entries
- no
- Used in current PDB entries
- Yes, in about 0.001 % of entries
Item Description
The angle (recip-alpha) defining the reciprocal cell in degrees.
(recip-alpha), (recip-alpha) and (recip-alpha) related to the
angles in the real cell by:
cos(recip-alpha)
= [cos(beta)*cos(gamma) - cos(alpha)]/[sin(beta)*sin(gamma)]
cos(recip-beta)
= [cos(gamma)*cos(alpha) - cos(beta)]/[sin(gamma)*sin(alpha)]
cos(recip-gamma)
= [cos(alpha)*cos(beta) - cos(gamma)]/[sin(alpha)*sin(beta)]
Ref: Buerger, M. J. (1942). X-ray Crystallography, p. 360.
New York: John Wiley & Sons Inc.
Data Type 
- Data type code
- float
- Data type detail
- float item types are the subset of numbers that are the floating numbers.
- Primitive data type code
- numb
- Regular expression
- -?(([0-9]+)[.]?|([0-9]*[.][0-9]+))([(][0-9]+[)])?([eE][+-]?[0-9]+)?
- Default value
- 90.0
- Units
- degrees
Allowed Boundary Conditions
| Minimum Value | Maximum Value |
|---|---|
| 0.0 | 180.0 |
Related Items 
| Related Item Name | Relation Type |
|---|---|
| _cell.reciprocal_angle_alpha_esd | associated_esd |
Aliases
| Alias Item Name | Dictionary Name | Dictionary Version |
|---|---|---|
| _cell_reciprocal_angle_alpha | cif_core.dic | 2.3 |